Emi Takahashi¹, Rebecca D Folkerth², Albert M Galaburda³, and P. Ellen Grant^1
1Children's Hospital Boston, Boston, MA, United States, ²Brigham and Women's Hospital, ³Beth Israel Deaconess Medical Center

We applied high-angular resolution diffusion imaging (HARDI) tractography to intact whole postmortem fetal human brains to explore the 3-dimensional regression of the radial and tangential migration pathways. Our results show the usefulness of HARDI tractography to image both radial and tangential migrational streams in fetal human brains, and suggest that regional regression of radial organization and regional emergence of fetal brain axonal connectivity proceed in general from postero-dorsal to antero-ventral with local variations related to the later appearance of gyri and sulci.

Cedric Clouchoux^1,2, Dimitri Kudelski³, Ali Gholipour⁴, Simon K Warfield⁴, Sophie Viseur⁵, Jean-Luc Mari³, Alan C Evans², Adre J DuPlessis¹, and Catherine Limperopoulos^1,2
1Children's National Medical Center, Washington, DC, United States, ²Montreal Neurological Institute, Montreal, QC, Canada, ³LSIS, Marseille, France, ⁴Children’s Hospital Boston, Boston, MA, United States, ⁵Universite de Provence, Marseille, France

Recent advances in fetal magnetic resonance imaging and post-processing computational methods are providing new insights into fetal brain maturation in vivo. To date, no study has delineated the gyrification process for the in vivo fetal brain. Herein, we investigate the in vivo fetal cortical folding between 25 and 35 weeks gestational age in healthy fetuses, using 3D reconstructed fetal cortical surfaces. We describe for the first time the in vivo fetal gyrification process using an original feature extraction algorithm applied directly on the cortical surface, providing an explicit delineation of the sulcal pattern during fetal brain development.

Piotr A. Habas¹, Julia A. Scott¹, Vidya Rajagopalan¹, Kio Kim¹, A. James Barkovich¹, Orit A. Glenn¹, and Colin Studholme^1
1University of California San Francisco, San Francisco, CA, United States

We present the results of spatially unconstrained detection and mapping of folding delays in fetuses with IMVM. MR imaging was performed for 16 IMVM subjects at 22.00-25.43GW and 22 age-matched controls. For each subject, a motion-corrected 3D MRI was reconstructed from multiple stacks of SSFSE T2w slices. Temporal changes in local curvature of the inner cortical surface were represented using a general linear model with a delay term for IMVM subjects. Significant folding delays were detected bilaterally along the parieto-occipital sulcus of IMVM subjects. Analysis with older fetuses will determine whether these differences are transient or persist into later gestation.

Gareth Ball¹, James P Boardman^1,2, Daniel Rueckert³, Paul Aljabar³, Tomoki Arichi^1,4, Nazakat Merchant^1,4, Ioannis S Gousias¹, A David Edwards^1,4, and Serena J Counsell^1
1Imperial College London and MRC Clinical Sciences Centre, London, United Kingdom, ²Simpson Centre for Reproductive Health, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom, ³Department of Computing, Imperial College London, London, United Kingdom, ⁴Division of Neonatology, Imperial College Healthcare NHS Trust, London, United Kingdom

Preterm birth is a leading cause of cognitive impairment in childhood, and is associated with a spectrum of structural brain abnormalities but the nature and evolution of these developmental processes are poorly understood. Using multi-modal magnetic resonance image analysis we demonstrate a specific pattern of cerebral growth that is related linearly to gestational age at birth, and show that thalamic size is directly related to the integrity of developing white matter tracts. These findings confirm that diminished thalamic growth and alterations in white matter microstructure occur in parallel after premature birth, possibly representing downstream consequences of a common primary insult.

Mathieu Dehaes^1,2, Rudolph Pienaar², Janet S Soul³, and P. Ellen Grant^1,2
1Division of Newborn Medicine, Department of Medicine, Children’s Hospital Boston, Harvard Medical School, Boston, Massachusetts, United States, ²Center for Fetal-Neonatal Neuroimaging & Developmental Science, Boston, Massachusetts, United States, ³Department of Neurolory, Children’s Hospital Boston, Harvard Medical School, Boston, Massachusetts, United States

Pseudo-continuous Arterial Spin Labeling (pCASL) can improve our understanding of metabolic changes that occur with injury by providing quantitative information on cerebral blood flow (CBF). Here we report our initial experience with pCASL in the first four months of life including two neonates and four young infants. Three subjects were imaged within 24 hours of cardiac arrest and 2 of 3 showed marked whole brain elevated CBF indicating rebound hyperperfusion. pCASL has tremendous potential in improving our understanding of physiological changes with injury. Better characterization of normal subject is needed to determine if there are more subtle increases in CBF.

Claudia Testa¹, Caterina Tonon¹, David Neil Manners¹, Emil Malucelli¹, Sara Grandi², Francesca Sbravati², Giacomo Faldella², Gina Ancora², and Raffaele Lodi^1
1MR Spectroscopy Unit, Department of Internal Medicine, Aging and Nephrology, University of Bologna, Bologna, Italy, ²Neonatology Unit, Department of Woman, Child and Adolescent Health, University of Bologna, Bologna, Italy

¹-MRS and DTI were evaluated in 19 neonates with hypoxic-ischemic encephalopathy after brain cooling. MRS was acquired in the basal ganglia, in white and gray matter; DTI was acquired using 15 gradient directions. Metabolites ratios and concentrations, MD and FA maps were calculated. ROIs were semi-automatically drawn onto each FA and MD map using study specific templates. NAA and mI resulted significantly lower in the basal ganglia and white matter of neonates with pathological outcome and the MD and FA values significantly reduced in ROIs of the supratentorial region suggesting that MR parameters predict the pathological outcome after brain cooling.

Richa Trivedi¹, Abhishek Yadav², Gyanendra Kumar Malik³, Archana Yadav³, Ram KS Rathore⁴, and Rakesh Kumar Gupta^2
1Institute of Nuclear Medicine and Allied Sciences, New Delhi, Uttar Pradesh, India, ²Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, Lucknow, Uttar Pradesh, India, ³Paediatrics, Chhatrapati Sahu ji Maharaj Medical University, Lucknow, Uttar Pradesh, India, ⁴Mathematics & Statistics, Indian Institute of Technology, Kanpur, Kanpur, Uttar Pradesh, India

Serial diffusion tensor tractography using FACT algorithm was performed on 11 term neonates with moderate hypoxic ischemic encephalopathy (HIE) to look for the change over time of the DTI measures in thalamic radiations in these infants compared to age/sex matched healthy controls through their early infancy. On comparing FA and MD changes over time, we observed altered patterns of age-related FA increase and MD decrease in thalamic radiations in neonates with HIE compared with controls. Our study suggests that abnormal FA and MD values with near normal conventional imaging may allow early and more accurate assessment of injury in neonates with HIE.

Arabhi C Nagasunder^1,2, Rafael Ceschin³, Robin L Haynes⁴, Jessica Wisnowski^1,5, Jane Tavare⁶, Marvin D Nelson¹, Stefan Bluml^1,2, Lisa Paquette⁷, and Ashok Panigrahy^1,3
1Radiology, Childrens Hospital Los Angeles, Los Angeles, CA, United States, ²Rudi Schulte Research Institute, Santa Barbara, CA, United States, ³Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA, United States, ⁴Pathology, Children's Hospital Boston, Boston, MA, United States, ⁵Brain and Creativity Institute, University of Southern California, Los Angeles, CA, United States, ⁶Division of Pathology, Childrens Hospital Los Angeles, Los Angeles, CA, United States, ⁷Division of Neonatology, Childrens Hospital Los Angeles, Los Angeles, CA, United States

Preterm infants are highly vulnerable to a spectrum of cognitive visual disturbances. Here we demonstrate that high risk preterm infants with periventricular leukomalacia (PVL) show significant correlation between thalamic volume and microstructural abnormalities in central visual pathways (optic radiation, splenium). In contrast, preterms infants without PVL demonstrate a milder version of the same injury pattern suggesting that damage to central visual pathways is not always associated with PVL. Thalamic injury may play a pivotal role in the pathogenesis of cognitive visual impairment in survivors of prematurity.

Deanne Kim Thompson^1,2, Terrie E Inder^1,3, Gehan Roberts¹, Jeremy Lim¹, Lex W Doyle^1,4, Peter J Anderson¹, and Gary F Egan^2
1Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia, ²Florey Neurosciences Institute, Centre for Neuroscience, University of Melbourne, Parkville, Victoria, Australia, ³Department of Pediatrics, St Louis Children's Hospital, Washington University in St Louis, St Louis, United States, ⁴Department of Obstetrics and Gynecology, Royal Women's Hospital, Parkville, Victoria, Australia

Motor dysfunction is commonly associated with preterm birth, but its neurological correlates are not well understood. Corpus callosum alterations have been implicated in impaired motor functioning. Structural and diffusion MR imaging at term equivalent age was used to assess differences between very preterm 5 year-olds with (n=20) and without motor impairment (n=69). Corpus callosum area, tract volume, and diffusion measures were obtained. Children with motor impairment demonstrated significantly lower mean, axial and radial diffusivity and higher FA within the callosal tracts, particularly posteriorly. These findings suggest that motor impairment common to very preterm children is partially explained by altered posterior callosal development.

Elda Fischi-Gomez¹, François Lazeyras², Cristina Borradori-Tolsa³, Jean-Philippe Thiran¹, and Petra S. Hüppi^3
1Signal Processing Laboratory 5 (LTS5), Ecole Politechnique Federale de Lausanne, Lausanne, Vaud, Switzerland, ²Service of Radiology, University Hospital of Geneva, Geneva, Switzerland, ³Division of Development and Growth. Department of Pediatrics, University of Geneva, Geneva, Switzerland

Survival of children born prematurely or with very low birth weight has increased dramatically in the last decades, but the long term developmental outcome remains a concern. The most common cerebral neuro-pathology observed in case of premature birth is a diffuse white matter abnormality. However, many of the children born prematurely present indeed deficits in their cognitive capacities, in particular involving executive domains. The origins of these disabilities are largely unknown but are likely to involve an overriding central nervous system deficit. To understand the neurostructural origin of these disabilities and to investigate the effect of prematurity and intra uterine growth restriction in pre-school children aged 6 years old, we have combined imaging with DWI and TBSS.